MANCHESTER, New Hampshire (CNN) -- Democratic presidential hopefuls traded barbs over the war in Iraq Sunday night in New Hampshire, with former Sen. John Edwards blasting two rivals for not taking the lead on a recent war spending bill.

Edwards said his opponents "have been quiet" on calling for a plan to withdraw U.S. troops from Iraq.

"They went quietly to the floor of the Senate, cast the right vote -- but there is a difference between leadership and legislators," Edwards said at the Democratic presidential debate in Manchester, New Hampshire.

"The importance of this is, they're asking to be president of the United States," he said. "And there is a difference between making clear, speaking to your followers, speaking to the American people about what you believe needs to be done, and I think all of us have a responsibility to lead on these issues."

Edwards voted for the October 2002 resolution that authorized the invasion of Iraq, but now calls that vote a mistake.

"You're about four and a half years late on leadership on this issue," Obama said "And, you know, I think it's important not to play politics on something that is as critical and as difficult as this."

Hillary Clinton also voted to authorize the March 2003 invasion, but the New York senator and former first lady said she was supporting "coercive diplomacy" by pressuring Iraq to allow U.N. weapons inspectors into the country.

But she said President Bush short-circuited the inspections to launch the war; and when it came time to vote on another $100 billion in war spending, "I thought the best way to support our troops was to send a very strong message that they should begin to come home." (Gallery: Behind the scenes at the debate)

Edwards later acknowledged Obama "deserves credit for being against this war from the beginning." And Clinton added, "The differences between us are minor. The differences between us and the Republicans are major."

Kucinich: 'The money's in the pipeline'

Rep. Dennis Kucinich, D-Ohio, an early and outspoken opponent of the invasion who mounted an anti-war campaign in 2004, said the way to end the war was to cut off funding.

"The money's in the pipeline right now, enough to bring the troops home," he said. "Let's end the war, and let's make this a productive evening."

But Sen. Joseph Biden, D-Delaware, said opponents of the war need to realize Democrats do not have the 67 votes needed to override a veto and force an end to the war.

"As long as there is a single troop in Iraq that I know if I take action by funding them, I increase the prospect they will live or not be injured, I cannot and will not vote no to fund them," said Biden, the chairman of the Senate Foreign Relations Committee.

Former Alaska Sen. Mike Gravel, who served in the Senate during the Vietnam War, said anyone who voted to authorize the invasion should not be president.

"We have killed more Americans than was done on the 11th of September," Gravel said. "More Americans died because of their decision. That disqualifies them for president."

The last question was from a local schoolteacher who asked what each candidate would make top priority in the first 100 days in office.

Clinton said she would end the war in Iraq. Obama echoed that goal, and added he would "get moving" on health care. Biden also topped his list with ending the Iraq war, and said he would defuse tensions with Iran and North Korea. Gravel said he would work to convince Democratic congressional leadership to end the war now.

Sen. Christopher Dodd of Connecticut said he would restore constitutional rights damaged by the Bush administration. New Mexico Gov. Bill Richardson said he would improve American education. Kucinich's top priority was to help "reshape the world for peace." And Edwards said he would travel the world to "re-establish America's moral authority." (Read full text of each candidate's response)

First time face-off in New Hampshire

Sunday's face-off at St. Anselm College was the first time the Democratic contenders shared a stage in New Hampshire, home of the nation's first presidential primary. The debate was staged by CNN, WMUR and the New Hampshire Union Leader. (Read what CNN's experts thought of the debate)

The war was expected to dominate discussion -- particularly after the heated congressional debate on the spending bill and the Democratic leadership's decision to drop calls for a withdrawal after Bush's May 1 veto.

Nearly 3,500 U.S. troops have been killed in in Iraq, and the war is now widely unpopular. New Hampshire state Sen. Lou D'Allesandro, a Manchester Democrat, said the war has hit close to home in New Hampshire "because of the number of National Guard people there."

"You are witnessing your friends and neighbors passing away or being killed," said D'Allesandro, who has not yet endorsed a candidate.

Clinton has held a consistent lead in recent polls, averaging 41 percent in a CNN survey of national polls in May. Obama trailed with 26 percent, while Edwards rounded out the top tier at 14 percent.

Biden, Kucinich, Richardson and Dodd trailed far behind, with support in the low single digits. Gravel's support failed to hit 1 percent.

Some common ground among the contenders

The hopefuls shared some common ground during Sunday's face-off in Saint Anselm's hockey arena. All nine said they would repeal the U.S. military's "don't ask, don't tell" policy barring homosexuals from serving openly, and all but Gravel said they would oppose making English an official language.

The candidates said they would work toward extending health insurance to all Americans. Clinton, who took on that task in a failed effort during her husband's presidency, said she was "thrilled" to see the issue back on the agenda.

"The most important thing is not the plan, because there are only a few ways to do this," she said. "And we're all talking pretty much about the same things. From my perspective, we have to lower cost, improve quality and cover everybody."

But Kucinich said the other candidates' proposals all assume that private insurers would extend coverage.

"We need a president who is ready to challenge that," said Kucinich, who favors a Canadian-style single-payer system. "And I'm ready to challenge the insurance companies."

The Granite State's primary -- historically a make-or-break contest for presidential campaigns -- is set for January 22. Front-runners go into New Hampshire hoping to demonstrate their strength, while underdogs try to use its tradition of informal, "retail" politics to engineer a breakthrough.

The 10 Republican presidential hopefuls will face off on the same stage at 7 p.m. ET Tuesday.